Smith sold 45 of his DVDs and purchased 10 more. If Smith has 15 DVDs now, how many DVDs did he have to begin with?

Question

Mathematics

Katrina Gaines

6 March, 14:16

Smith sold 45 of his DVDs and purchased 10 more. If Smith has 15 DVDs now, how many DVDs did he have to begin with?

+3

Answers (2)

Know the Answer?

Thalia · Answer 1

"x" represents the DVDs Smith began with:

(x-45) + 10=15

Sold (-) 45, bought (+) 10, has (=) 15

Solve for x:

(x-45) + 10-10=15-10

x-45=5

x-45+45=5+45

x=50

Devan Haas · Answer 2

Let's set up a formula for this, where x is the amount of dvds he started with:

x-45+10=15

x-35=15

+35 + 35

x=50

He had 50 DVDs to begin with.

Check

50-45+10

=15